title: Preparation of unconventional dendrimers that contain rigid NH-triazine linkages and peripheral tert-butyl moieties for CO2 -selective adsorption.
abstract: Three unconventional dendrimers that contained rigid NH-triazine linkages and peripheral tert-butyl moieties were prepared by using a convergent approach and characterized by (1)H and (13)C NMR spectroscopy, mass spectrometry, and elemental analysis. Based on a thermogravimetric analysis study, these dendrimers were observed to display thermal stability at about 300 °C. The NH-triazine moiety, which possessed protonated and proton-free nitrogen sites (like the imidazole unit), displayed the capture of polarizable CO2 molecules through hydrogen-bond and/or dipole-quadrupole interactions. In addition, the adsorption of various amounts of CO2 and N2 at different pressures suggests that the dendritic pores, which arise from the stacking of the middle co-planar and rim protuberant dendrimers, Gn -N∼N-Gn (n=1-3), either swell or shrink at high pressure, thus indicating that these dendrimers may have a breathing ability.
authors.affiliation: Department of Applied Chemistry, National Chi Nan University, No.1 University Rd., Puli, Nantou, Taiwan.
authors.forename: Cheng-Hua
authors.initials: CH
authors.lastname: Lee
authors.forename: Meng-Rong
authors.initials: MR
authors.lastname: Tsai
authors.forename: Yen-Tzu
authors.initials: YT
authors.lastname: Chang
authors.forename: Long-Li
authors.initials: LL
authors.lastname: Lai
authors.forename: Kuang-Lieh
authors.initials: KL
authors.lastname: Lu
authors.forename: Kung-Lung
authors.initials: KL
authors.lastname: Cheng
keywords: adsorption; carbon dioxide; dendrimers; heterocycles; pores